delegate aliases

gistfile1.rb

# code I found (i.e. not mine)

class Module
  def metaclass(&block)
    meta = class << self; self; end
    meta.module_eval(&block) if block_given?
    meta
  end

  def const_delegate(to,*methods)
    mc = to.metaclass
    methods.each do |(source,target)|
      mc.class_eval "def #{target || source}(*args); #{self}.#{source}(*args); end"
    end
  end
end

# this was in an initializer
Tripyn.const_delegate Airport,
  [:airport_for_iata_code, :for],
  [:airport_for_iata_code!, :for!],
  [:airport_for_iata_code, :for_iata_code],
  [:airport_for_iata_code!, :for_iata_code!],
  [:airport_for_fs_code, :for_fs_code],
  [:airport_for_fs_code!, :for_fs_code!],
  [:closest_airport_to, :closest_to]

#---------------------------------------------------------------
# option 1
# kinda clunky, but no meta-programming and it uses only existing solutions

class Airport
  class << self
    delegate :all_airports,
             :airport_for_iata_code,
             :airport_for_iata_code!,
             :airport_for_iata_code,
             :airport_for_fs_code,
             :airport_for_fs_code!,
             :closest_airport_to,
             :to => Tripyn

    alias_method :all, :all_airports
    alias_method :for, :airport_for_iata_code
    alias_method :for!, :airport_for_iata_code!
    alias_method :for_iata_code, :airport_for_iata_code
    alias_method :for_iata_code!, :airport_for_iata_code!
    alias_method :for_fs_code, :airport_for_fs_code
    alias_method :for_fs_code, :airport_for_fs_code!
    alias_method :closest_to, :closest_airport_to
  end
end

#---------------------------------------------------------------
# option 2
# extends module, but still pretty straightforward

class Module
  def delegate_aliases(to, *aliases)
    aliases.each do |(source, target)|
      delegate target, :to => to
      alias_method source, target
    end
  end
end

class Airport
  class << self
    delegate_aliases Tripyn,
      [:for, :airport_for_iata_code],
      [:for!, :airport_for_iata_code!],
      [:for_iata_code, :airport_for_iata_code],
      [:for_iata_code!, :airport_for_iata_code!],
      [:for_fs_code, :airport_for_fs_code],
      [:for_fs_code!, :airport_for_fs_code!],
      [:closest_to, :closest_airport_to]
  end
end